Question

A book is pushed off the edge of a table. At what point during the fall will the potential and kinetic energy be equal?

Answer 1

Answer:

KE = PE at half the table Height:

Explanation

AT ANY POINT IN THE BOOK'S FALL,

TOTAL E = PE +KE

THE TOTAL E IS CONSTANT

Before the book is pushed off, the total energy is potential

TOT E=PE =MGH

BEFORE THE BOOK HITS THE GROUND, THE TOTAL E IS KINETIC

TOT=KE = MVXV/2

WHEN KE = PE

KE+PE = MGH (STARTING ENERGY SINCE E IS CONSERVED)

OR PE+ PE = MGH

OR MGH' + MGH' =MGH

OR 2H' =H

H' (NEW HEIGHT) =H/2